On Tue, Sep 01, 2015 at 11:36:25PM +0530, Sivakumar Thulasimani wrote: > > > On 8/20/2015 10:07 PM, ville.syrjala@xxxxxxxxxxxxxxx wrote: > > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > > > We are no longer checkling the DP link status on long hpd. We used to do > > that from the .hot_plug() handler, but it was removed when MST got > > introduced. > > > > If there's no userspace we now fail to retrain the link if the sink > > power is toggled (or cable yanked and replugged), meaning the user is > > left staring at a blank screen. With the retraining put back that should > > be fixed. > > > > Also remove the leftover comment that referred to the old retraining > > from .hot_plug(). > > > > Fixes a regression introduced in: > > commit 0e32b39ceed665bfa4a77a4bc307b6652b991632 > > Author: Dave Airlie <airlied@xxxxxxxxxx> > > Date: Fri May 2 14:02:48 2014 +1000 > > > > drm/i915: add DP 1.2 MST support (v0.7) > > > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89453 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91407 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89461 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89594 > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=85641 > > Cc: Dave Airlie <airlied@xxxxxxxxxx> > > Cc: stable@xxxxxxxxxxxxxxx > > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_dp.c | 11 +++++------ > > 1 file changed, 5 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > > index d32ce48..b014158 100644 > > --- a/drivers/gpu/drm/i915/intel_dp.c > > +++ b/drivers/gpu/drm/i915/intel_dp.c > > @@ -5024,9 +5024,12 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) > > > > intel_dp_probe_oui(intel_dp); > > > > - if (!intel_dp_probe_mst(intel_dp)) > > + if (!intel_dp_probe_mst(intel_dp)) { > > + drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); > > + intel_dp_check_link_status(intel_dp); > > + drm_modeset_unlock(&dev->mode_config.connection_mutex); > couple of queries for my understanding. > > why should we check for link status for long pulse, which is supposed > to be for plug in or plug out ? > > goto mst_fail will indicate we are falling back to intel_dp_detect, > isnt this better suited there ? ->detect() should do what it says and no more. In any case I think it's better to have the code to maintain the current link in one place. That should also make the locking rules easier to understand since we hpd_pulse and detect are executed from different works. > > Also the following bug indicates failure in mst panel, but the changes > here are in non-mst path > https://bugs.freedesktop.org/show_bug.cgi?id=89453, how is this > patch helping this bug ? Presumably the monitor is being used in non-MST mode. > > goto mst_fail; > > - > > + } > > } else { > > if (intel_dp->is_mst) { > > if (intel_dp_check_mst_status(intel_dp) == -EINVAL) > > @@ -5034,10 +5037,6 @@ intel_dp_hpd_pulse(struct intel_digital_port *intel_dig_port, bool long_hpd) > > } > > > > if (!intel_dp->is_mst) { > > - /* > > - * we'll check the link status via the normal hot plug path later - > > - * but for short hpds we should check it now > > - */ > > drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); > > intel_dp_check_link_status(intel_dp); > > drm_modeset_unlock(&dev->mode_config.connection_mutex); > > -- > regards, > Sivakumar -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
